JPH10273891A - Production of paper containing bacterial cellulose - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for producing the sheet in a high filler yield, even when the filler is compounded in a large amount, by adding bacterial cellulose dispersed under a specific condition into wood pulp. SOLUTION: This method for producing the bacterial cellulose-containing paper comprises adding a prescribed amount of the bacterial cellulose to wood pulp. Therein, the dispersion of the bacterial pulp is produced by subjecting a bacterial cellulose dispersion to a ultrasonic dispersion treatment using a sonolator controlled so that the Brookfield viscosity of the dispersion is a prescribed value under a specific condition.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a paper having high filler retention containing bacterial cellulose, and more particularly, to a method for preparing a high-filled paper.
The present invention relates to a method for producing paper containing bacterial cellulose which has excellent filler retention and operability.

[0002]

2. Description of the Related Art Bacterial cellulose is edible and tasteless and odorless, so it is used in the field of foods, and because of its excellent water-based dispersibility, it maintains the particle size of foods, cosmetics, paints, etc. It is industrially useful as a fortification, water retention, food stability improvement, low calorie additive or emulsion stabilization aid. As other fields, Acetobacter xylina as disclosed in JP-A-59-120159 is disclosed.
It is also known to use the gel produced by inum) ATCC 23769 as a medical pad. On the other hand, regarding the use of bacterial cellulose in a sheet, see JP-A-63-1.
As disclosed in JP-A-99201, the content of α-cellulose is improved by treating the gel with an alkaline solution or a bleaching agent to obtain a sheet having a high elasticity. It is known to obtain a highly opaque paper by incorporating a water-insoluble or sparingly soluble inorganic substance into a gel as disclosed.

[0003] Dispersion treatment is required to make bacterial cellulose into paper and exhibit its properties. The dispersion phenomenon of bacterial cellulose is considered to be a phenomenon in which a stress generated inside the cellulose due to a mechanical external force or the like deforms or breaks the stress. Therefore, the dispersion treatment of the bacterial cellulose is performed by applying a mechanical external force to the bacterial cellulose. The mechanical external force referred to herein includes, for example, stress such as tension, bending, compression, torsion, impact, and shear, but generally, compression, impact, and shear stress are mainly contained.

Therefore, conventionally, such a dispersion treatment for applying a mechanical external force to bacterial cellulose has been performed using, for example, a mixer, a polytron or an electric vibration type ultrasonic oscillator. The gazette also discloses various dispersion methods.

However, the disintegration of bacterial cellulose described in JP-A-8-291201 focuses on the effect as a thickener, and the effect of improving the yield of filler for papermaking is not mentioned at all. Not.

[0006]

Generally, high-quality paper used for printing paper, writing paper, etc., contains a filler for the purpose of improving opacity, smoothness and whiteness of the paper. ing. As these fillers have smaller particle size, the desired properties are improved, so it is desirable to use as fine particles as possible.However, under actual papermaking conditions, when dewatering on a wire, the filler having a small particle size is combined with water. There was a problem that it was easily washed away. For this reason, a method of actually adding a retention aid such as an acrylamide polymer to aggregate the filler to cause the retention in paper has been used, but the problem that improving the retention results in deterioration of formation. was there. On the other hand, a method of adding a filler to cells of wood pulp has also been proposed, but could not contain a high filler.

[0007] It is an object of the present invention to remedy the conventional problems by using bacterial cellulose. Especially,
In the present invention, by dispersing the bacterial cellulose under specific conditions, the filler holding capacity of the bacterial cellulose is directly increased, and by blending this with wood pulp, even in a high filler blending, the paper yield with improved filler retention is improved. It has been successfully manufactured.

[0008]

Means for Solving the Problems As a result of various studies to solve the above problems, the present inventors conducted an ultrasonic dispersion treatment on bacterial cellulose with a sonolator and determined the degree of the dispersion. By defining the Brookfield viscosity of the dispersion under the conditions, it has been found that the filler retention effect of bacterial cellulose is enhanced even in a high filler formulation. By blending a certain amount of this bacterial cellulose dispersion into wood pulp, a bacterial cellulose-containing paper excellent in filler yield and operability can be obtained, and thus a method for producing the bacterial cellulose-containing paper of the present invention has been invented. .

That is, according to the present invention, when the bacterial cellulose is dispersed based on a weight concentration of 0.1%, the Brookfield viscosity measured at a dispersion temperature of 35 ° C. and a BL rotor of 60 rpm is 35 cps.
As described above, a bacterial cellulose-containing paper is produced by using a dispersion of the bacterial cellulose which has been subjected to ultrasonic dispersion treatment by a sonator and containing the bacterial cellulose in an amount of 5% by weight or less of the total pulp amount. It is a manufacturing method.

In the above invention, it is preferable that the bacterial cellulose is produced by aeration and stirring culture.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, a method for producing bacterial cellulose-containing paper of the present invention will be described in detail.

A feature of the method for producing a bacterial cellulose-containing paper of the present invention is that, in a paper containing 5% by weight or less of the total pulp content, the bacterial cellulose to be blended is dispersed on the basis of 0.1% by weight. The Brookfield viscosity measured at a rotation speed of 60 rpm using a BL rotor at a dispersion temperature of 35 ° C. is 35.
The production may be performed by performing an ultrasonic dispersion treatment using a sonolator so as to be at least cps.

In the present invention, the bacterial cellulose content is preferably not more than 5% by weight of the total pulp content. Bacterial cellulose has a high hydration property because the fibril fragment width is about two orders of magnitude smaller than cellulose produced from wood pulp and the like. The blended raw materials are inferior in drainage in the papermaking process, and the productivity is greatly deteriorated.

The bacterial cellulose used in the present invention is any one of cellulose produced by microorganisms, heteropolysaccharide having cellulose as a main chain, and glucans such as β-1,3, β-1,2 and the like. A mixture of them. The components other than cellulose in the case of the heteropolysaccharide,
Hexoses, such as mannose, fructose, galactose, xylose, arabinose, rhamnose, and glucuronic acid;

The cellulose-producing bacteria producing bacterial cellulose used in the present invention are, for example, BPR2001
Acetobacter xylinum spp.
lnum subsp.sucrofermentans), Acetobacter xyllnum ATCC23768, Acetobacter xylinum ATCC23769, Acetobacter xylinum
A. pasteurlanus ATCC10245, Acetobacter xylinum ATCC14851, Acetobacter xylinum ATCC11142 and Acetobacter
Acetic acid bacteria (genus Acetobacter) such as Xylinum ATCC 10821; These are various mutant strains created by subjecting them to mutation treatment by a known method using NTG (nitrosoguanidine) or the like. The BPR2001 strain was deposited on February 24, 1993 at the Patented Microorganisms Depositary Center, National Institute of Bioscience and Human-Technology, Ministry of International Trade and Industry (Accession No. FERM P-1346).
6) and subsequently transferred to a deposit based on the Budapest Treaty on the International Recognition of Patent Deposits on February 7, 1994 (Accession No. FERM BP-4545).

In the present invention, the bacterial cellulose to be blended is preferably subjected to a self-excited ultrasonic dispersion treatment using a sonolator. The feature of self-excited ultrasonic dispersion processing is
Since continuous processing is possible, reproducibility is good, and driving operation is extremely simple, it is suitable for industrial mass processing. Also,
Regarding the dispersion of bacterial cellulose by the self-excited ultrasonic oscillator, it is estimated that cavitation (cavitation phenomenon) occurs continuously in the medium due to the oscillation of the ultrasonic oscillator, and the significant shear force generated locally is mainly dominant. Is done.

[0017] Bacterial cellulose depends on dispersion conditions.
Filler yield effect is greatly affected. Even if the dispersion is slight or excessive, the filler retention effect cannot be sufficiently exerted. However, in the present invention, when the dispersion is carried out on the basis of a weight concentration of 0.1%, the number of rotations of the bacterial cellulose dispersion using a BL rotor is 60 rpm, the dispersion temperature is 35. It is preferable that the Brookfield viscosity measured at the condition of ° C. is 35 cps or more, preferably 37 cps or more.
Brookfield viscosity measured under the same conditions is 35 cps
If the amount is less than the above, the bacterial cellulose is not sufficiently dispersed, or the dispersion of the bacterial cellulose is excessive, so that the filler retention rate decreases.

Bacterial cellulose used in the present invention has been conventionally used in a culture method for culturing microorganisms, that is, for example, stationary culture, shaking or aerated culture, or a so-called batch fermentation method or a fed-batch method known as a culture operation method. It can be produced by batch fermentation, repeated batch fermentation, continuous fermentation, and the like. Among them, those produced by aeration and agitation culture are preferable.

The stirring culture is a culture method in which the culture solution is stirred while the culture is stirred, and the structure of the bacterial cellulose, for example, the crystallization index decreases and the amorphous part Changes to increase. As the stirring means, for example, an impeller, an air-lift fermenter, a pump-driven circulation of fermentation broth, a combination of these means, and the like can be used.

As the type of filler used in the bacterial cellulose-containing paper of the present invention, a conventionally known white pigment can be used. For example, light calcium carbonate, heavy calcium carbonate, kaolin, clay, talc, calcium sulfate, barium sulfate, titanium dioxide, zinc oxide, zinc sulfide, zinc carbonate, satin white, aluminum silicate, diatomaceous earth, calcium silicate, magnesium silicate, Synthetic silica, aluminum hydroxide, alumina,
White inorganic pigments such as lithopone, zeolite, magnesium carbonate and magnesium hydroxide, styrene-based plastic pigments, acrylic-based plastic pigments, polyethylene, microcapsules, and organic pigments such as urea resin and melamine resin.

The wood pulp used for the bacterial cellulose-containing paper of the present invention includes NBKP, LBKP, NBS
In addition to P, LBSP, GP, TMP, etc., used paper pulp may be mentioned, and may be used alone or in combination as needed.

The raw materials for waste paper pulp referred to in the present invention include: top white, ruled white, cream white, card, and the like shown in the waste paper standard quality standard table of the Waste Paper Recycling Promotion Center.
Special white, medium white, imitation, fair white, Kent, white art, special top cut,
Another example is newspaper, magazine, etc. Further specific examples include uncoated computer paper, which is information-related paper,
Printer paper such as thermal paper, pressure sensitive paper, etc., OA waste paper such as PPC paper, coated paper such as art paper, coated paper, lightly coated paper, matte paper, or high quality paper, color high quality, notebook, stationery, wrapping paper , Fancy paper, medium paper, newsprint, paper change, super wrapping paper, imitation paper, pure white roll paper,
Waste paper such as uncoated paper such as milk carton and paperboard, and chemical pulp paper, high-yield pulp-containing paper, etc. are used, but printing, copying, printing and non-printing are not particularly limited. Absent.

In the present invention, other additives such as a pigment dispersant, a thickener, a flow improver, an antifoaming agent, a foam inhibitor, a release agent, a foaming agent, a penetrant, Coloring dyes, coloring pigments, fluorescent whitening agents, ultraviolet absorbers, antioxidants, preservatives, anti-binders, water-proofing agents, wet paper strength enhancers, dry paper strength enhancers, etc. to achieve the desired effects of the present invention. It can also be appropriately compounded within a range that does not impair.

In the papermaking method of the paper containing bacterial cellulose of the present invention, the papermaking machine is a well-known papermaking machine such as a fourdrinier paper machine, a twin wire paper machine, a combination paper machine, a round net paper machine, a Yankee paper machine or the like. Can be used as appropriate.

[0025]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail with reference to embodiments. The present invention is not limited to the embodiments. “Parts” and “%” in the following are parts by weight and% by weight unless otherwise specified.

[Preparation Example of Stirred Cultured Bacterial Cellulose] (1) Preparation of Seed Bacteria (Proliferation of Bacterial Cells) Cellulose-producing bacteria were grown by a flask culture method. 40 g / L fructose, 1.0 g / L phosphate-potassium, 0.3 g / L magnesium sulfate, 3 g / L ammonium sulfate, 5 g / L bacto-peptone, 1.4 ml / L lactic acid, 100 ml basic medium with initial pH 5.0
Into a 750 ml Roux flask filled with
1 ml of a cryopreserved strain of the 2001 strain (FERM BP-4545) was inoculated, and the Roux flask was shaken well, and the contents were filtered under a sterile condition with gauze to obtain a seed bacterial solution. (2) Production of Bacterial Cellulose by Stirred Culture 60 ml of the above-described seed bacterial solution was aseptically inoculated into a sterilized small jar fermenter (total volume: 1000 ml) into which 540 ml of a stirrer culture medium to be described later was stuck.
While controlling the pH to 5.0 with ammonia gas or 1N H ₂ SO ₄ for 20 hours or 30 hours, and at the initial rotation of 400 rpm, the dissolved oxygen content (D
Agitating culture was performed with a jar fermenter while automatically controlling the number of revolutions so that O) was within 3.0 to 21.0%. For the stirring culture, a medium having the following composition was used.

[0027]

[Table 1]

[0028]

[Table 2]

[0029]

[Table 3]

After the completion of the culture, the solid matter in the jar fermenter was accumulated, and the medium was removed by washing with water.
The cells were treated at 80 ° C. overnight in an aOH aqueous solution to remove the cells. Further, after neutralization with sulfuric acid, the resulting cellulose was washed with water until the washing solution became nearly neutral to obtain purified bacterial cellulose. The bacterial cellulose obtained was granular pellets.

[Dispersion Example 1 of Stirred Cultured Bacterial Cellulose] Water was added to the above granular pellets at a concentration of 0.2%, and a flow rate of 6 L / min and a pressure of 100 kg were applied using a sonolator (manufactured by SONIC). / Cm ² , the orifice opening area 0.001 inch ² , the back pressure valve and the blade position are adjusted so that the sound pressure is maximized, and the dispersion process is performed once per pass. I got The weight concentration of this dispersion is 0.1%, the number of rotations using a BL rotor is 60 rpm, and the dispersion temperature is 35 ° C.
Brookfield viscosity measured under the conditions of 39 cps
Met.

[Dispersion Example 2 of Stirred Cultured Bacterial Cellulose] Water was added to the above granular pellets to a concentration of 0.2%, and a flow rate of 6 L / min, a pressure of 70 kg / cm ² , and an orifice was used using a sonolator. Open area 0.001i
Dispersion was performed once per pass under the conditions that the back pressure valve and the blade position were adjusted so that nch ² and the sound pressure were maximized, to obtain a dispersion 2 of bacterial cellulose. The Brookfield viscosity measured at a concentration of 0.1% by weight of the dispersion, a rotation speed of 60 rpm using a BL rotor and a dispersion temperature of 35 ° C. was 37 cps.

[Dispersion Example 3 of Stirred Cultured Bacterial Cellulose] Water was added to the above granular pellets so that the concentration became 0.5%, and 10% under the maximum rotation condition using a mixer (manufactured by Ooster Co.). A dispersion treatment was performed for a minute to obtain a dispersion 3 of bacterial cellulose. 0.1% by weight of the dispersion, a rotation speed of 60 rpm using a BL rotor,
The Brookfield viscosity measured at a dispersion temperature of 35 ° C. was 33 cps.

[Preparation Example 1 of Stationary Cultured Bacterial Cellulose] A test tube slant agar medium (pH 6.
The BPR2001 strain grown at 30 ° C. for 3 days at 0) was inoculated into the same medium as above, one platinum loop at a time, and cultured at 30 ° C.

After culturing for 15 days under the above conditions, a white bacterial cellulosic polysaccharide was added to the upper layer of the culture solution at 0.1%.
A 5 mm thick gel film containing 5% was formed. This gel film was washed with water and used as a sample in an undried state.

[Dispersion Example 1 of Stationary Cultured Bacterial Cellulose] The above gel-like membrane was roughly pulverized with a commercially available blender with a blade, and then water was added to a concentration of 0.2%.
Using a sonolator, flow rate 6 L / min, pressurization 100 kg /
cm ^2, the orifice opening area 0.001Inch ^2, as the sound pressure becomes maximum, performed through the number one dispersion treatment under the conditions adjusted back pressure valve and blade position, the variance of static culture bacterial cellulose Liquid 1 was obtained. The concentration of the dispersion is 0.1% by weight, and the number of rotations is 60 using a BL rotor.
The Brookfield viscosity measured at 35 rpm and a dispersion temperature of 35 ° C. was 35 cps.

Example 1 Bacterial cellulose in the stirred bacterial cellulosic dispersion of Dispersion Example 1 and unbeaten LBKP (freeness 450 c)
c) was mixed in a weight ratio of 2:98, and 100 parts of light calcium carbonate (TP-121 manufactured by Okutama Kogyo KK) and positive starch (Cato: manufactured by National Starch & Chemical Co., Ltd.) were added thereto.
3210) 1 part was added, and the filler yield was determined using this slurry. The amount of the filler was determined at 500 ° C,
Ashing was performed in 4 hours.

Example 2 In Example 1, bacterial cellulose and unbeaten LBKP were used.
Example 2 was carried out in the same manner except that (freeness: 450 cc) was changed to a weight ratio of 5:95.

Example 3 In Example 1, bacterial cellulose and unbeaten LBKP were used.
Example 3 was carried out in the same manner except that (freeness: 450 cc) was changed to a weight ratio of 3:97.

Example 4 The procedure of Example 4 was repeated, except that the bacterial cellulose of Dispersion Example 2 was used instead of the bacterial cellulose of the stirred culture bacterial cellulose dispersion of Dispersion Example 1.
And

Example 5 The procedure of Example 3 was repeated, except that the stationary culture bacterial cellulose of Dispersion Example 1 was used instead of the bacterial cellulose of the stirred culture bacterial cellulose dispersion of Dispersion Example 1.
Example 5 was used.

COMPARATIVE EXAMPLE 1 Comparative Example 1 was carried out in the same manner as in Example 3 except that the bacterial cellulose of Dispersion Example 3 was used instead of the bacterial cellulose of the stirred and cultured bacterial cellulose dispersion of Dispersion Example 1.
And

Comparative Example 2 In Example 1, unbeaten LBKP (freeness: 450 cc), 100 parts of light calcium carbonate, and 1 part of positive starch were added without adding bacterial cellulose, and further an acrulamide-based retention improver (HYMO (NR-11LS), 250 ppm relative to pulp. Comparative Example 2 was made in the same manner except that this slurry was used.

Comparative Example 3 In Example 3, microfibrillar cellulose (manufactured by Daicel, Selish FD-10) was used in place of bacterial cellulose in the stirred bacterial cellulose dispersion of Dispersion Example 1.
Comparative Example 3 was made in the same manner except that E) was used.

The freeness, the filler retention rate and the viscosity of the samples of Examples 1 to 5 and Comparative Examples 1 and 2 were measured by the following methods, and the evaluation results were summarized in Table 1 below. Show.

1) Freeness: A pulp slurry obtained by mixing a filler, a papermaking chemical, and a bacterial cellulose dispersion (Comparative Example 2 does not contain a bacterial cellulose dispersion) is JIS.
The Canadian standard freeness (CSF) was measured according to P-8121. The freeness needs to be 200 cc or more, and preferably 250 cc or more, for stable papermaking in an actual machine.

2) Filler yield: pulp slurry obtained by mixing a filler, papermaking chemicals and a bacterial cellulose dispersion (Comparative Example 2 does not contain a bacterial cellulose dispersion)
Was calculated based on the TAPPI standard method T-261 from the amount passed through the screen. The amount of calcium carbonate was calculated according to JIS P-8128 except that the combustion temperature and time were set at 500 ° C. for 4 hours. In a high filler composition such as the present composition, the filler yield is desirably 40% or more.

3) Viscosity: The viscosity of the bacterial cellulose dispersion was measured using a B-type viscometer (manufactured by TOKIMEC: DVL-B).
The Brookfield viscosity was measured using II) under the conditions of a weight concentration of 0.1%, a rotation speed of 60 rpm using a BL rotor, and a dispersion temperature of 35 ° C.

[0049]

[Table 4]

As is clear from Table 4 above, the pulp slurry containing bacterial cellulose was as follows:
It can be seen that as the content increases, the filler yield rate improves (Examples 1 to 3). In addition, it was found that the one containing the stationary-cultured bacterial cellulose was excellent in the freeness, but the filler yield effect was inferior to that of the stirring culture (Example 5).

On the other hand, when the bacterial cellulose is not contained in the pulp slurry, the filler retention rate is greatly reduced (Comparative Example 2). Also, when the dispersion processing was performed by a mixer instead of a sonolator,
There is a problem with the filler yield (Comparative Example 1). Further, when microfibril cellulose was contained instead of bacterial cellulose, it was found that the filler retention rate was significantly reduced as in Comparative Example 1 (Comparative Example 3).

[0052]

According to the present invention, by including bacterial cellulose in a prescribed amount in wood pulp, it is possible to obtain a method for producing bacterial cellulose-containing paper which is excellent in filler yield even with a high filler content. The bacterial cellulose dispersion is subjected to an ultrasonic dispersion treatment with a sonolator in which the degree of dispersion is defined by the Brookfield viscosity of the dispersion under specific conditions, whereby the filler retention effect of the bacterial cellulose can be increased. .

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Hiroo Kaji 3-4-2, Marunouchi, Chiyoda-ku, Tokyo Mitsui Paper Co., Ltd. (72) Inventor Hiroshi Ogiya 3-2-1, Sakado, Takatsu-ku, Kawasaki-shi, Kanagawa Prefecture No. Biopolymer Research Co., Ltd. (72) Inventor Otsuhiko Watanabe 3-2-1 Sakado, Takatsu-ku, Kawasaki-shi, Kanagawa Prefecture Biopolymer Research Co., Ltd. (72) Inventor Shinya Hioki Takatsu, Kawasaki-shi, Kanagawa 3-2-1 Sakado-ku, Tokyo Biopolymer Research Inc.

Claims (2)

[Claims] In the dispersion of bacterial cellulose based on a weight concentration of 0.1%, a dispersion temperature of 35.degree.
The Brookfield viscosity measured under the condition that the L rotor has a rotation speed of 60 rpm is 35 cps or more,
A method for producing a bacterial cellulose-containing paper, comprising using a dispersion of the bacterial cellulose subjected to ultrasonic dispersion treatment by a sonolator and incorporating the bacterial cellulose into 5% by weight or less of the total pulp amount. 2. The method for producing bacterial cellulose-containing paper according to claim 1, wherein the bacterial cellulose is produced by aeration and stirring culture.